Under international law, crimes against humanity include “murder and other inhumane acts carried out against any civilian population… when such acts are done or such persecutions carried on in execution of or in connection with any crime against peace or any war crime.”
A war crime is an act that constitutes a “serious violation of the laws of war that gives rise to individual criminal responsibility and include intentionally killing civilians… destroying civilian property… and serious violations of the principles of distinction and proportionality, such as strategic bombing of civilian populations.”
Note: First part is the standard mantra against Germany.